Answer:
I am pronounced as one letter written with three. I come in blue black brown or grey. Reverse me and I read the same either way.
Take off my skin I won't cry but you will.
What building has the most stories?
What goes through cities and fields but never moves?
I am rarely touched but often held and if you are smart you'll use me well.
Give it food and it will live, give it water and it will die.